Heat sink



FIG. 1 is a top perspective view of a heat sink, showing my new design;

FIG. 2 is a bottom perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a left side elevational view thereof;

FIG. 6 is a right side elevational view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof.

The broken lines within the hexagram shaped openings in FIG. 7illustrate portions of the heat sink and form no part of the claimeddesign.

CLAIM The ornamental design for a heat sink, as shown and described.